//
// Created by Jisam on 24/08/2024 8:46 PM.
// Solution of  P1094纪念品分组
//#pragma GCC optimize(3)
#include <bits/stdc++.h>

using namespace std;
#define endl "\n"
#define PSI pair<string,int>
#define PII pair<int,int>
#define PDI pair<double,int>
#define PDD pair<double,double>
#define VVI vector<vector<int>>
#define VI vector<int>
#define VS vector<string>
#define PQLI priority_queue<int, vector<int>, less<int>>
#define PQGI priority_queue<int, vector<int>, greater<int>>
#define code_by_jisam ios::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr)
using namespace std;
using u32 = unsigned;
using i64 = long long;
using u64 = unsigned long long;
using i128 = __int128;
int dx[] = {-1, 1, 0, 0, 1, 1, -1, -1,};
int dy[] = {0, 0, -1, 1, 1, -1, -1, 1,};

void solution() {
    int w,n;
    cin >> w >>n;
    VI a(n);
    for(auto &x : a){cin >> x;}
    sort(a.begin(),a.end());
    int l = 0,r = n -1;
    int ans = 0;
    while(l <= r){
        if(a[l]+a[r]<=w)   //一定要有等号。
            l++,r--,ans++;
        else
            r--,ans++;   //贪心过程
    }
    cout << ans;
}

int main() {
    code_by_jisam;
    int T = 1;
//    cin >> T;
    while (T--) {
        solution();
    }
    return 0;
}